Do not let the server load chunks from newer versions

If the server attempts to load a chunk generated by a newer version of
the game immediately stop the server to prevent data corruption.

You can override this functionality at your own peril.

1 files changed, 40 insertions, 0 deletions

diff --git a/Spigot-Server-Patches/0443-Do-not-let-the-server-load-chunks-from-newer-version.patch b/Spigot-Server-Patches/0443-Do-not-let-the-server-load-chunks-from-newer-version.patch
new file mode 100644
index 0000000000..07cef370ee
--- /dev/null
+++ b/Spigot-Server-Patches/0443-Do-not-let-the-server-load-chunks-from-newer-version.patch
@@ -0,0 +1,40 @@
+From 93a3a2f86bd4571ff2d8e3a66ba2c2d97f79356a Mon Sep 17 00:00:00 2001
+From: Zach Brown <[email protected]>
+Date: Tue, 23 Jul 2019 20:44:47 -0500
+Subject: [PATCH] Do not let the server load chunks from newer versions
+
+If the server attempts to load a chunk generated by a newer version of
+the game, immediately stop the server to prevent data corruption.
+
+You can override this functionality at your own peril.
+
+diff --git a/src/main/java/net/minecraft/server/ChunkRegionLoader.java b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
+index dce52ac0f..9c22e343a 100644
+--- a/src/main/java/net/minecraft/server/ChunkRegionLoader.java
++++ b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
+@@ -288,8 +288,22 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
+         }
+     }
+ 
++    // Paper start
++    private static final int CURRENT_DATA_VERSION = 1631;
++    private static final boolean JUST_CORRUPT_IT = Boolean.valueOf("Paper.ignoreWorldDataVersion");
++    // Paper end
++
+     @Nullable
+     protected Object[] a(GeneratorAccess generatoraccess, int i, int j, NBTTagCompound nbttagcompound) { // CraftBukkit - return Chunk -> Object[]
++        // Paper start - Do NOT attempt to load chunks saved with newer versions
++        if (nbttagcompound.hasKeyOfType("DataVersion", 3)) {
++            int dataVersion = nbttagcompound.getInt("DataVersion");
++            if (!JUST_CORRUPT_IT && dataVersion > CURRENT_DATA_VERSION) {
++                new RuntimeException("Server attempted to load chunk saved with newer version of minecraft! " + dataVersion + " > " + CURRENT_DATA_VERSION).printStackTrace();
++                System.exit(1);
++            }
++        }
++        // Paper end
+         if (nbttagcompound.hasKeyOfType("Level", 10) && nbttagcompound.getCompound("Level").hasKeyOfType("Status", 8)) {
+             ChunkStatus.Type chunkstatus_type = this.a(nbttagcompound);
+ 
+-- 
+2.22.0
+